← All changes | modules/tiled-gallery/math/class-constrained-array-rounding.php +108 -0 16.2-beta → 16.3-beta View file →

		@@ -1,0 +1,108 @@
	1	+<?php // phpcs:ignore WordPress.Files.FileName.InvalidClassFileName
	2	+
	3	+/**
	4	+ * Lets you round the numeric elements of an array to integers while preserving their sum.
	5	+ *
	6	+ * Usage:
	7	+ *
	8	+ * Jetpack_Constrained_Array_Rounding::get_rounded_constrained_array( $bound_array )
	9	+ * if a specific sum doesn't need to be specified for the bound array
	10	+ *
	11	+ * Jetpack_Constrained_Array_Rounding::get_rounded_constrained_array( $bound_array, $sum )
	12	+ * If the sum of $bound_array must equal $sum after rounding.
	13	+ *
	14	+ * If $sum is less than the sum of the floor of the elements of the array, the class defaults to using the sum of the array elements.
	15	+ */
	16	+class Jetpack_Constrained_Array_Rounding {
	17	+ /**
	18	+ * Get the rounded constrained array.
	19	+ *
	20	+ * @param array $bound_array - the array we're rounding.
	21	+ * @param int $sum - the sum of the array.
	22	+ *
	23	+ * @return array
	24	+ */
	25	+ public static function get_rounded_constrained_array( $bound_array, $sum = false ) {
	26	+ // Convert associative arrays before working with them and convert them back before returning the values
	27	+ $keys = array_keys( $bound_array );
	28	+ $bound_array = array_values( $bound_array );
	29	+
	30	+ $bound_array_int = self::get_int_floor_array( $bound_array );
	31	+
	32	+ $lower_sum = array_sum( wp_list_pluck( $bound_array_int, 'floor' ) );
	33	+ if ( ! $sum || ( $sum < $lower_sum ) ) {
	34	+ // If value of sum is not supplied or is invalid, calculate the sum that the returned array is constrained to match
	35	+ $sum = array_sum( $bound_array );
	36	+ }
	37	+ $diff_sum = $sum - $lower_sum;
	38	+
	39	+ self::adjust_constrained_array( $bound_array_int, $diff_sum );
	40	+
	41	+ $bound_array_fin = wp_list_pluck( $bound_array_int, 'floor' );
	42	+ return array_combine( $keys, $bound_array_fin );
	43	+ }
	44	+
	45	+ /**
	46	+ * Get int floor of array values.
	47	+ *
	48	+ * @param array $bound_array - the array we're getting floor values for.
	49	+ *
	50	+ * @return array
	51	+ */
	52	+ private static function get_int_floor_array( $bound_array ) {
	53	+ $bound_array_int_floor = array();
	54	+ foreach ( $bound_array as $i => $value ) {
	55	+ $bound_array_int_floor[ $i ] = array(
	56	+ 'floor' => (int) floor( $value ),
	57	+ 'fraction' => $value - floor( $value ),
	58	+ 'index' => $i,
	59	+ );
	60	+ }
	61	+
	62	+ return $bound_array_int_floor;
	63	+ }
	64	+
	65	+ /**
	66	+ * Adjust the constrained array.
	67	+ *
	68	+ * @param array $bound_array_int - the array we're adjusting.
	69	+ * @param int $adjustment - how much we're adjusting the array.
	70	+ */
	71	+ private static function adjust_constrained_array( &$bound_array_int, $adjustment ) {
	72	+ usort( $bound_array_int, array( self::class, 'cmp_desc_fraction' ) );
	73	+
	74	+ $start = 0;
	75	+ $end = $adjustment - 1;
	76	+ $length = count( $bound_array_int );
	77	+
	78	+ for ( $i = $start; $i <= $end; $i++ ) {
	79	+ ++$bound_array_int[ $i % $length ]['floor'];
	80	+ }
	81	+
	82	+ usort( $bound_array_int, array( self::class, 'cmp_asc_index' ) );
	83	+ }
	84	+
	85	+ /**
	86	+ * Compare fraction values of two arrays.
	87	+ *
	88	+ * @param array $a - the first array we're comparing.
	89	+ * @param array $b - the second array we're comparing.
	90	+ *
	91	+ * @return int
	92	+ */
	93	+ private static function cmp_desc_fraction( $a, $b ) {
	94	+ return $b['fraction'] <=> $a['fraction'];
	95	+ }
	96	+
	97	+ /**
	98	+ * Compare index values of two arrays.
	99	+ *
	100	+ * @param array $a - the first array.
	101	+ * @param array $b - the second array.
	102	+ *
	103	+ * @return int
	104	+ */
	105	+ private static function cmp_asc_index( $a, $b ) {
	106	+ return $a['index'] <=> $b['index'];
	107	+ }
	108	+}